Related art imaging apparatuses, such as printers, may include two sets of mechanical assemblies to detect the size of media received on a media tray. A first mechanical assembly includes various types of guide members, brackets, levers, stoppers, etc., located on the media tray, which are adjusted for adapting to the length and width of the media received in the tray. Based on the media size, the components move to a distinct receiving position in the tray, and create a predetermined pattern of projections and depressions that are unique to that media size.
When the related art media tray is pushed into a tray slot in the printer, the first mechanical assembly triggers a unique set of media sensing levers that are located on the media tray or inside the tray slot. For example, the first mechanical assembly may trigger a first set of media sensing levers for a letter-sized paper, and a second set of sensing levers for a legal-sized paper. Although these sensing levers are evenly spaced, there is an inherent uneven-spacing between the group of levers corresponding to the length of the media and the group of levers corresponding to the width of the media.
The triggered sensing levers then activate a second mechanical assembly including switches, springs, shafts, metal parts, and plastic components, which in turn send signals to a printed circuit board (PCB) placed beneath this assembly. The second mechanical assembly involves a complex design, and can engage with only evenly-spaced sensing strips, and does not account for the uneven spacing. As a result, the second assembly uses a large number of parts to separately engage unevenly-spaced length sensing levers and width sensing levers. This causes a significant increase in assembly time, manufacturing complexity and cost of the printer. It may, therefore, be advantageous to provide a simple and cost-effective mechanical assembly for detecting the media size.